1689027521 has 4 divisors (see below), whose sum is σ = 1691583444. Its totient is φ = 1686471600.

The previous prime is 1689027451. The next prime is 1689027539. The reversal of 1689027521 is 1257209861.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1539699121 + 149328400 = 39239^2 + 12220^2 .

It is a cyclic number.

It is not a de Polignac number, because 1689027521 - 2²⁶ = 1621918657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1689027581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1276970 + ... + 1278291.

It is an arithmetic number, because the mean of its divisors is an integer number (422895861).

Almost surely, 2^1689027521 is an apocalyptic number.

It is an amenable number.

1689027521 is a deficient number, since it is larger than the sum of its proper divisors (2555923).

1689027521 is an equidigital number, since it uses as much as digits as its factorization.

1689027521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2555922.

The product of its (nonzero) digits is 60480, while the sum is 41.

The square root of 1689027521 is about 41097.7800008711. The cubic root of 1689027521 is about 1190.9099085573.

The spelling of 1689027521 in words is "one billion, six hundred eighty-nine million, twenty-seven thousand, five hundred twenty-one".